Coil Checking & Replacement Options

[foxxinabox at wideopenwest.com (foxxinabox@xxxxxxxxxxxxxxxx)]

  Am I to assume that the coils on our cars either work or they don't? Just
curious in regards to my '85 burning rich and occasionally stumbling under
full throttle though the timing is set correctly and the fuel distributor is
set midway between rich and lean.
  I also have a number of coils from parts cars and was wondering if there is
a way to test them other than simply installing them (with an ohm meter, perhaps).
  Lastly, when in the parts store it appears that MSD makes a coil of similar
size for $46. Is that something worth looking into or simply paying for a
name? Thanx.